Loctite - red or blue?

[stuchman1]

Hi everyone,

I've reviewed the forum and haven't found this specific question answered. If it's in there and I missed it, my apologies in advance!

We're working on our MK4. My question is about Loctite.

In the "stuff you need" beginning section of the manual, they just mention getting BLUE Loctite / threadlocker.

Then in various parts of the manual when they mention using Loctite, it's clearly RED in the picture. An example is when you're bolting the hub to the rear spindles. It says "use Loctite" and there's a nice red tube of Loctite with clearly red Loctite liquid on the bolt.

In other parts of the manual, such as with the ball joints on the front upper control arms, they clearly are using blue.

Which is better to use in those pics where it's red? May be a dumb question but I'm coming at this with just enough knowledge to be dangerous, so I want to check with the experts on this forum.

Thanks in advance!
ST

[egchewy79]

I believe red is only called for on the ball joints. blue everywhere else.
you'll need to use heat to remove red loctite.
176720176721
this is why I have trust issues :)

[toadster]

I'm no expert, but what makes it more unclear is their bottling colors, one would think that BLUE Loctite would be in a BLUE bottle, but nope - it's BLUE letters on a RED bottle

176719

blue is to hold from accidental loosening, any bolt can use blue within reason, things that are 'serviceable' usually use 'blue'
red is for higher performance securing - things like a driveshaft bolts and brake caliper bolts uses red - more prone to vibration and loosening, , or if you have a locknut in your application that's about as secure as red

[Ted G]

Honestly, either one will work on most applications. I use both and those things I probably won't ever remove, red is good. Others, I'll use blue.

[stuchman1]

I believe red is only called for on the ball joints. blue everywhere else.
you'll need to use heat to remove red loctite.
176720176721
this is why I have trust issues :)

LOL - That's the exact opposite of what's in the build manual. They have blue on ball joints and red on most other parts I've looked, including bolting hub to rear spindle, and also for the jam nut on the rear upper control arms. Trust issues indeed! :)

[Alan_C]

Here is an alternative to the Loctite Red, Permetex Orange thread locker. As you can read on the website, the orange has a high strength formula like the Loctite Red, but more like the Loctite Blue in terms of removability.

https://www.permatex.com/products/thread-compounds/orange-threadlockers/permatex-high-strength-removable-threadlocker-orange-gel-5-g/?location=3122%20Watson%20Lake%20Rd,%20Prescott,%2 0AZ%2086301,%20USA&radius=25

[JJK]

so now I am a bit worried as I used blue loctite for the ball joints per the manual but have found many posts on other threads indicating that may not be sufficient. I see several people recommend a tac weld on these to prevent backing out. Is this still recommended?

[DadofThree]

BLUE ONLY for me! And add Torque Paint, You WILL want to take things apart in the future. BLUE ONLY (in the red bottle)

[juddster]

When I had my custom driveline made the guy said to use red for that type of application. I used blue mostly everywhere else.

[edwardb]

This subject is discussed frequently. Surprised you didn't find any previous threads. But that's OK. My take (and fair warning for opinions...). Order of importance for bolting one of these together: (1) Proper torque. Can't emphasize that enough. (2) Multiple examples of locknuts with inserts or distorted threads. Nothing further required. (3) Blue Loctite. (4) Red Loctite where it's explicitly called out. As already stated, it typically takes heat to break red loose. For small diameter bolts, you may find that they break off before letting go. Ask me how I know. I'm only aware of a couple spots in the build where red is called out. Factory Five had an engineering update a few years ago where they wanted you to use it on the adjusters on the 2015+ IRS. Along with witness marks. Wilwood calls it out on some of their directions. There may be a few others, but you get the point. My personal rule is unless it's specifically called out, I don't use red on anything I expect to have to take apart in the future. I wouldn't put a lot of stock in the pictures in the manual. They're often stock pictures that may/may not be specific to the current version or what you're working on. If in doubt, be careful not to take them too literally. Front upper ball joints are fine with blue. Again, put witness marks on them and make it part of your annual PM. If properly tightened, I'll bet you won't see them move. Witness marks are actually good anywhere you're even slightly concerned. I used a red paint pen. But there are dedicated products like Dykem.

Just a general comment. Seems builders, especially new builders, are concerned these things shake or vibrate enough to loosen or shed bolts. Properly built and set up, you're going to find that's not the case. Good assembly practice, again focusing on the right hardware and the right torque values, and that's not going to happen. Of course along with an annual PM that checks things over just to be sure. Take a look at your average daily driver. Which undergo significant long term testing, vibration, etc. The factories put a huge emphasis on the proper torques. But Loctite type products are only used in a very limited number of spots. And typically it's pre-applied on the bolts. Like flywheel bolts, driveshaft bolts, and a few others. So while using Loctite certainly doesn't hurt anything, it's not something that should keep you awake at night if you're following good build practices.

[Gizmosrcool]

Blue for 99%. Red if its called for. And I may question that. It does make it very hard to get off.

My Harley's for 30 years have blue on every nut/bolt I twist. If a Milwaukee V-twin cant shake it loose. Blue is pretty good.

[Mike.Bray]

As mentioned above, proper torque is what is most important to keep fasteners tight. Here's a link to a post I did better explaining how fasteners work and stay tight.

https://thefactoryfiveforum.com/showthread.php?42292-Why-the-Torque-Wrench-is-Your-Best-Friend

[RoadRacer]

Just as a counterpoint - I only own red, and it's all I use. I've never used heat to remove, and after I've undone something I use a wire brush wheel to clean it all.

I know it's not right, but if I'm locking something, I want it locked. e.g. grub screws on the steering column. My car is pretty stiffly sprung and driven hard on bad roads. *shrug*

Most things are of course nyloc or lock nuts anyway.

[narly1]

And for fasteners #6 and smaller there is pink Loctite.

Earl

[stuchman1]

Extremely helpful discussion. Thank you also much. ST

[Jessew]

Just as a counterpoint - I only own red, and it's all I use. I've never used heat to remove, and after I've undone something I use a wire brush wheel to clean it all.

I know it's not right, but if I'm locking something, I want it locked. e.g. grub screws on the steering column. My car is pretty stiffly sprung and driven hard on bad roads. *shrug*

Most things are of course nyloc or lock nuts anyway. Same. I’ve used red on countless Harley’s and hot rods. Never had to use heat to remove. I had one chopper that would not stay together no matter what. Red wouldn’t even hold some fasteners on.

[Dgc333]

Find this discussion interesting. I am building a 33 and with the exception of a few places (grub screws on steering, drive shaft to rear end) every fastener on the chassis has a lock nut. The only place where loctite is called out is

[Sharris2]

Don't worry about it; you'll give yourself gray hair. You did use cotter pins; right

[Andrew Davis]

That's why I was smiling, safety wiring my Wilwood rotors.

[Windsor]

And for fasteners #6 and smaller there is pink Loctite.

I think you mean "Purple" -- 222 (which also comes in a red tube/bottle). It's good stuff and works well for bigger fasteners too, less "stuck" than blue but still some effort required to remove.

What edwardb said earlier -- I only use red if I expect to never undo it.